Realization of a quadrupole topological insulator phase in a gyromagnetic photonic crystal.

ABSTRACT: The field of topological photonics was initiated with the realization of a Chern insulator phase in a gyromagnetic photonic crystal (PhC) with broken time-reversal symmetry (T), hosting chiral edge states that are topologically protected propagating modes. Along a separate line of research, a quadrupole topological insulator was the first higher-order topological phase supporting localized corner states, but has been so far limited to T-invariant systems, as T is a key ingredient in early models. Here we report the realization of a quadrupole topological insulator phase in a gyromagnetic PhC, as a consequence of topological phase transition from the previously demonstrated Chern insulator phase. The phase transition has been demonstrated with microwave measurements, wh

SUBMITTER: Zhou P 

PROVIDER: S-EPMC11493087 | biostudies-literature | 2024 Nov

REPOSITORIES: biostudies-literature